Everyone expected Jason Altmire to face a messy primary battle this spring with fellow Democrat Mark Critz, after their Western Pennsylvania congressional districts were essentially combined under redistricting.

No one expected Altmire to be unseated by something as rudimentary as failing to get 1,000 valid signatures on nominating petitions.

Yet that is exactly what happened late last week, when the Critz campaign challenged 950 of the 1,600 signatures on Altmire's petitions.

"Everyone knows the rules and what is expected," Mikus said. "The fact that the Altmire campaign (collected) only 1,651 signatures, most of which are invalid, shows that his campaign has some very serious organizational issues."

Mikus might know a little about Altmire's operation: He worked on Altmire's 2008 re-election campaign.

The 12th District once was a center of national attention because of Jack Murtha, the colorful, powerful congressman from Johnstown for more than 35 years. Even he had to battle a fellow Democrat, Frank Mascara, when their districts were combined following the 2000 census.

Murtha beat Mascara handily in a battle so bitter that Mark Singel, a former acting governor, is pretty sure both went to their graves never speaking again.

"Fair to say that animosity lingered to the end," Singel said.

"This is a pretty unusual situation," said Geoffrey Skelley, a University of Virginia Center for Politics analyst. The closest comparison he can recall was when former Congressman Charlie Wilson of Ohio failed to make the ballot for lack of signatures and "had to run a write-in campaign to win the Democratic nomination."

Washington Democrats parachuted in and produced way more signatures than Wilson needed. He went on to win the general election.

"This episode shows that Altmire's team ... did a poor job of executing a straightforward task, which reflects poorly on the congressman," said Skelley.

The only explanation that comes to mind is that redistricting left the political boundaries up in the air until December.

Still, Critz's team collected more signatures than Altmire's -- and most of the new district is Altmire's old turf.

"Even more damning," according to Skelley, "is the fact that 385 of the 942 signatures being contested by Critz were collected by an Altmire staffer who lives outside the district, which isn't allowed under Pennsylvania law."

The requirements are pretty clear, he said, yet Altmire's staff may have made enough mistakes to cost him a place on the primary ballot.

Pitting incumbents against each other is a classic majority-party strategy to wound the opposition. We see such battles every 10 years, following redistricting.

In Ohio, the districts of longtime Democrat U.S. Reps. Dennis Kucinich and Marcy Kaptur were pushed together by the Republican-controlled legislature.

Washington Democrats say they are worried that Altmire may be permanently damaged by not making the ballot or residually damaged going into the general election with a negative narrative about his capabilities.

Washington Republicans are thrilled: They consider Altmire tougher to beat than Critz.

They are classic centrist-conservative Western Pennsylvania Democrats. Obama won just 45 percent of the vote in Altmire's old district and less than 50 percent in Critz's, so each is are capable of winning in fairly purple territory.

The new 12th is about a 45-percent Obama district. So Altmire, having held a Republican-"redder" district in the past and having represented more of the new 12th, indeed might have a better chance than Critz of winning the general election , according to Skelley.

Even without this party spat, or even in a non-presidential year, this district would be front and center in national coverage: It leans right, could easily be held by a conservative Democrat, and is home to voters whom Obama once referred to as bitter and clinging to God, Bibles and guns.